Private branch exchange



FIG. 1 is a top perspective view of a private branch exchange of thepresent invention;

FIG. 2 is a front view thereof;

FIG. 3 is a first side view thereof;

FIG. 4 is a second side view thereof;

FIG. 5 is a top view thereof;

FIG. 6 is a bottom view thereof; and,

FIG. 7 is a rear view thereof.

A private branch exchange, or PBX, is a telephone switch for offices,for example.

The broken lines immediately adjacent the shaded areas, which define theunshaded regions, represent the bounds of the claimed design. All otherbroken lines are directed to environment and are for illustrativepurposes only. The broken lines and unshaded regions within the brokenlines form no part of the claimed design.

I claim the ornamental design for a private branch exchange, as shownand described.